<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>

    </style>
</head>

<body>
    <input type="text" id="i1">
    <input type="text" id="i2">
    <input type="button" value="加" onclick="f(1)">
    <input type="button" value="减" onclick="f(2)">
    <input type="button" value="乘" onclick="f(3)">
    <input type="button" value="除" onclick="f(4)">
    <div>结果：</div>

    <script>
        let i1 = document.querySelector("#i1");
        let i2 = document.querySelector("#i2");
        let d = document.querySelector("div");
        function f(x) {
            if (isNaN(i1.value) || isNaN(i2.value)) {
                d.innerHTML = "王冉婷大傻蛋";
                return;
            }
            switch (x) {
                case 1:
                    d.innerHTML = "结果：" + (parseFloat(i1.value) + parseFloat(i2.value));
                    break;
                case 2:
                    d.innerHTML = "结果：" + (parseFloat(i1.value) - parseFloat(i2.value));
                    break;
                case 3:
                    d.innerHTML = "结果：" + (parseFloat(i1.value) * parseFloat(i2.value));
                    break;
                case 4:
                    d.innerHTML = "结果：" + (parseFloat(i1.value) / parseFloat(i2.value));
                    break;
            }
        }
        // }
        // function jia() {
        //     if (isNaN(i1.value) || isNaN(i2.value)) {
        //         d.innerHTML = "王冉婷大傻蛋";
        //         return;
        //     }
        //     d.innerHTML = "结果：" + (parseFloat(i1.value) + parseFloat(i2.value));
        // }
        // function jian() {
        //     if (isNaN(i1.value) || isNaN(i2.value)) {
        //         d.innerHTML = "王冉婷大傻蛋";
        //         return;
        //     }
        //     d.innerHTML = "结果：" + (parseFloat(i1.value) - parseFloat(i2.value));
        // }
        // function cheng() {
        //     if (isNaN(i1.value) || isNaN(i2.value)) {
        //         d.innerHTML = "王冉婷大傻蛋";
        //         return;
        //     }
        //     d.innerHTML = "结果：" + (parseFloat(i1.value) * parseFloat(i2.value));
        // }
        // function chu() {
        //     if (isNaN(i1.value) || isNaN(i2.value)) {
        //         d.innerHTML = "王冉婷大傻蛋";
        //         return;
        //     }
        //     d.innerHTML = "结果：" + (parseFloat(i1.value) / parseFloat(i2.value));
        // }
    </script>



</body>

</html>